<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<style>
			.box1 .a{
				color: #ff0;
			}
		</style>
	</head>
	<body>
		<div class="box1">
			<div class="a">123</div>
		</div>
		
		<div class="box2">
			<div class="a">456</div>
		</div>
		
	</body>
</html>
